Hack-saw machine



July 24, 1923- 11,462,779

R. WICKSTEED v- HACK SAW MACHINE Filed April 26. 1921 3 Sheets-Sheet l I v V G H ll lm M111! I W lium I "II" II NU-m July 24, 1923- 3.9462: R.VWCKSTEED HACK SAW MACHINE led p il 26. 1921 3 Sheets-Sheet 2 July 24, 1923- R. WICKSTEED HACK SAW MACHINE Filed April 26. 1921 5 Sheets-Sheet 5 Patented July 24, 1923.

aALrH'wIcKsTnnn, or KETTERING, ENGLAND.

T07 all whom it may concern Be it known thatl, RALPH Wronsrnnn,

a subject of the King of England, director of facture than those at present in use, and

yet shall be so constructed that it is easy to handle and its running parts readily kept in alignment so that it shall be eflicient in its output. It is well known that one'of the difiiculties with hack-saw machines, as atpresent manufactured, is that expensive bearings have to be provided for the saw-framearm, in order that the saw may run true and thatundue wear may not occur. It is particularly important that the saw-frame shall be prevented from lateral'movement in a horizontal plane, as thisresults in irregular cutting and breakage of saws, yet the construction of many of the existing machines issuch that, when wear occurs," it takes place in those partswhich are relied upon to retain the saw-frame against lateral movement, and the eflect of the wear is often magnified through the various'parts, so that a slight amount of wear at one point will' result in 'a considerable amount of lateral instability of the s'aw-frame. i

A hack-saw machine according to this invention, is characterized by the saw-frame arm, which is'flat-sided in the vertical plane, having as 'itsonly guide fiat-sided members opposed to the fiat sides of the arm and by the vertical depth of the bearing thus provided being considerably greater than the vertical'crosssection of the arm, so that the arm can atall times be freely raised and lowered in the bearing for the purpose of allowing the saw to descend as it cuts, and also to allow the saw to be raised without any 'specialadjustments to insert the work HACK-SAW MACHINE.

Application filed April as, 1921. Serial No. 464,586.

example, by nuts operating against the thrustof springs.

In the accompanying drawings, which illustrate one method of carrying out this invention,

Figure l is an elevation of the hack-saw machine,

Figure 2 is a plan of the same, and

Figure 3 is a section through the machine on the line 3-3 of Figure 1'.

Like letters indicate like parts throughout the drawings.

The frame'A is made integral with standards A and the vertical face of the frame is faced on two parts which lie beneath straps B. The saw-frame C is so constructed that it constitutes a closed figure across which the saw C is held under tension by the usual tighteningdevice C By making the sawframe in this form a cast iron frame can be used instead of a malleable casting, as it is strong enough to resist breakage by tightening up of the nut C whereasthe open frame, if made of cast iron, is liable to break under this stress;

The saw-frame arm D whereby the sawframe is reciprocated, lies between the flat surfaces provided by facing the frame, and the flat surfaces provided by the straps B opposed thereto; the faced parts of the frame and the'strips B constitute guide members and it will be observed thatthe vertical depth of the bearing thus afforded by its guide members for the arm D is considerably greater than the vertical depth of the arm itself, so that the arm can freely rise and fall in the hearing. The straps B are held in placeby nuts B carried by studs B and the said nuts operate against the thrust of springs B placed between the frame A. and the straps. It will thus be seen that the bearing can always be adjusted accurately to the arm as wear occurs by further tightening the nuts against thesprings.

The driving mechanism for the saw-frame comprises a shaft E carrying fast and loose pulleys F and a disc G whereonnis mounted a crank-pin G The crank-pin is surrounded by a block G whichislides in a slotted link H. i This link is vertically placed, and is pivoted at its lower end at E to one of the standards A of the "machine, and at its upperend by a pin H to the saw-frame arm. The saw-frame arm can" thus swing about the axis of this pivot pin'and is ree ciprocated by the thrust of the link applied through it.

The hack-saw end of the frame of the machine is slotted at A to receive a gripping arm J. This arm is pivoted to the frame of the machine at J and is pulled inwards by a tightening rod J controlled by a screwthreaded hand-wheel J which engages a screw-threaded end ofv the rod J 2 and bears against a boss A on the frame. A table A is provided at the side of the gripping arm so that the work can be laid thereon between the arm and a vertical face A of the frame, with the result that when the arm is tightened against it, the work is firmly held in place beneath the saw. The space between the cutting edge of the saw and the bottom of the'saw-frame, is suflicient to admit the largest bar or other piece of work which the machine is intended to accommodate. and it will be seen that the frame can at all times be lifted to insert the work without any prior adjustment. Thus if the machine is making successive cuts through a bar of metal and has completed one cut so that the sawframe drops to the limit of movement afforded by the bearings of the arm D, it is only necessary to commence sawing another section, to first lift the saw-frame arm and then feed the work forward through the space between the cutting edge of the saw and the bottom of the frame, after releasing the tightening screw J when the screw J 3 can be again tightened up and everything is ready for the next cut.

The loading of the saw is effected by a block K slidably mounted on a bar K This bar is pivoted to one of the standards A of the machine at K and at the other end is pivoted at' K to the lower end of a vertical link K*. The upper end of the link K is pivoted at K to the saw-frame, so that the weight is not reciprocated by the saw-frame, though it always retains a downward pull upon it. 'The rear of the bar K is run out beyond the pivot K and the weight can pass this pivot, being slotted for this purpose, as at S, so that, if desired, the weight can be run out on to this portion to reduce or eliminate its downward pull on the sawframe.

It will be seen that the character of beam ing for the arm D is inexpensive to produce and is such that the lateral play in a horizontal plane can at all times be made practically nil. If slight wear does occur in these hearings, the distance at which the two straps are placed apart prevents this wear from being appreciably magnified at the hack-saw end and as wear occurs it can be immediately followed up by adjusting the straps B closer to the vertical face of the frame; The bearing moreover, is inexpensive to produce as compared with "V-shaped guides and other more complicated bearings,

H permits of all the movements necessary,

for these purposes. nism, that is the crank-pin G with its block G and the link H is simple and inexpensive to manufacture and affords a quick return movement such as is desired for'machines of this class. Again, the gripping arm J working in the slot A constitutes inexpensive and efficient means for holding the work in place, instead of the usual expensive vice. All these parts therefore, co-operate to pro duce an efficient and inexpensive machine, and it is found in practice that such a ma chine can be operated at a'greater spe d than the more expensive machines now upon the market.

Obviously, details may he modified without departing from the spirit of this inven tion as defined in the claims.

What I claim as my invention and desire to secure by Letters Patent is:

1. In a hack saw machine, the combination of a machine frame, saw frame, a fiat sided arm attached to the saw frame, fiat sided guide members on said machine frame opposed to the flat sides of the arm and constituting a bearing in which said arm can reciprocate, which bearing is considerably greater in depth than the width of the arm, reciprocatory driving mechanism, and a horizontal pivot pin, about the longitudinal axis of which the said arm can swing operatively connecting, the arm with said driving mechanism, said bearing and said pivot 'pin constituting the sole means for guiding said arm. whereby the saw frame is free to rock vertically about the pivot pin in all positions of the driving mechanism, substanti ally as described.

2. In a hack saw machine, the combination of a machine frame, a saw frame, a fiat sided arm attached to the saw frame, said machine frame having a flat guide face opposed to one flat side of said arm, a guide member having a fiat guide face opposed to the other fiat side of said arm. adjustably mounted on the machine frame, a spring pressing on said guide member and tending to grip its guide face against the opposed face of said arm, said guide faces constituting a hearing which is considerably greater in depth than the width of the arm, reciprocatory driving mechanism and a horizontal pivot pin, about the longitudinal axis of which the. said-arm can swing, 10peratively connecting the arm'with said driv- 'ing mechanism, said bearing and said pivot pin constituting the sole means for guiding said arm, whereby the saw frame is free to rock vertically about the pivot in all The driving mechapositions of the driving mechanism, substantially as described.

3. In a hack sawmachine, the combina-.

tion of a machine. frame, saw frame, a flat sided arm attached to the saw frame, flat sided uide members on said machine frame 7 opposed to the flatsides of the arm and constituting a bearing in which said arm can reciprocate, which bearing is considerably I tion of a machine-frame, a saw-frame havgreater in depth than the width of the arm, reciprocatory driving mechanism comprising a slotted link pivotally mounted towards one end of it on the machine frame, a rotary driving member journalled in tlie machine frame and engaging said link in its slot, and a horizontal pivot pin operatively connecting said arm with the other end of said link, said bearing and said pivot pin constituting the sole means for guiding said arm, substantially as described. 4. In aback-saw machine, the combinaing a flat-sided arm, flat-sided guide members on said machine-frame opposed to the flat sides of the arm and constituting a bearing in which said arm can reciprocate, which bearing is considerably greater in depth than the width of the arm,-drivingmeans arranged to reciprocate said arm in said arm can reciprocate, a saw carried in said saw-frame in positional relation to said table, a grippingarm pivoted to said machine-frame below said table and extending above the same for gripping against said side of the machine-frame work that is supported on said table, tightening means mountedin the machine-fram and operatively connected with said gripping-arm above the table, and driving means arranged to reciprocate said arm in said bearing.

6. A hack-saw machine comprising in combination, a machine-frame having a horizontal wcrk-table arranged at right-angles to one side thereof, a saw-frame in the form of a closed figure having an external horizontal flat-sided arm guided with play in a vertical direction in two bearings spaced apart on the machine-frame; drivingmechanism comprising a slotted link pivotally mounted on the machine-frame and operatively connected to said arm and a rotary driving-member engaging said link between said bearings in its slot; a horizontal leverpivoted on the machine-frame below said arm, a link operatively connecting said lever with said saw-frame, and a weight adjustablycarried by said lever; a saw carried in said saw-frame in positional relatlon to said table; a gripping arm pivoted to said machine frame below said table and extending above the same for gripping against said side of the machine-frame work that is supported on said table, and tightening means mounted on the machine-frame and operatively connected with said gripping arm above the table.

In testimony whereof I affix my signature.

RALPH WICKSTEED. 

